July 2022 Summaries

There is no one-size-fits-all solution for guaranteeing webhook ordering, as it depends on various factors such as the specific use case and customer requirements. Ensuring ordering can be challenging due to issues like failed deliveries, slow handlers processing events out of order, and race conditions. To address these challenges, designers can opt for payloads that provide enough information for customers to process them in any order, including using thin payloads with identifiers and metadata, or including entity modification dates in the payload. Another approach is to attach a monotonically increasing sequence number to events, but this also comes with its own set of issues. Ultimately, the best solution is to design webhooks that don't require ordering, as forcing delivery order can be fragile and prone to errors.

There are several security risks associated with webhooks, including server-side request forgery (SSRF), spoofing attacks, replay attacks, and man-in-the-middle (MITM) attacks. To mitigate these risks, it's essential to implement measures such as signing webhooks with strong cryptographic primitives, using HTTPS URLs for encryption, and implementing idempotency and timestamp verification. Additionally, relying solely on IP allow lists is insufficient due to potential sharing of IPs between customers. Implementing secure authentication mechanisms like TLS can also help prevent these attacks, but it requires provisioning client certificates and handling mTLS complexities.

Tom Hacohen, CEO of Svix, sat down with Ken Ruf, Head of Growth at Svix, to discuss webhook architecture and best practices for sending webhooks at scale. They talked about scalability, security, developer experience, customer experience, and the importance of monitoring and visibility in a webhook system. Tom emphasized the need for retries, security measures such as signing requests and using HMAC, fan out to multiple services, filtering by event types, and providing visibility into delivery status. He also highlighted the importance of defining requirements upfront and considering factors like rate limiting to ensure smooth operation at scale.

We have successfully completed our SOC 2 Type II audit, and Svix is now SOC 2 Type II certified! This certification is more stringent than the previous SOC 2 Type I audit, which checked compliance at a certain point in time, whereas this audit assesses continued compliance over a longer period. The SOC 2 report focuses on five categories: security, availability, processing integrity, confidentiality, and privacy, to ensure trust and transparency with customers and business partners, especially in highly regulated industries. Svix has passed the audit with no exceptions, demonstrating its commitment to security, reliability, and integrity of the service.